Zheng Xu-Guang, Xu Chao-Nan, Uchiyama Tomoki, Yamauchi Ichihiro, Galica Tomasz, Nishibori Eiji, Chen Ying
Department of Materials Science and Engineering, Faculty of Engineering, Tohoku University, Sendai, 980-8579, Japan.
Department of Physics, Faculty of Science and Engineering, Saga University, Saga, 840-8502, Japan.
Adv Sci (Weinh). 2025 Jan;12(1):e2410977. doi: 10.1002/advs.202410977. Epub 2024 Nov 7.
Oxygen in solids usually exists in an O ionic state. As a result, it loses its magnetic nature of a single atom, wherein two unpaired electrons exist in its outer 2p orbitals. Here, it is shown that an unconventional stable ionic state of O is realized in a new semiconductor material SrAlO, leading to an intrinsic p-orbital ferromagnetism stable until ≈900 K. Experimental and theoretical investigations have clarified that one-fourth of the oxygen atoms in SrAlO are insufficiently bonded in the crystal structure, resulting in a unique O-state and p-orbital ferromagnetism. To date, the O state is reported to exist only in non-equilibrium conditions, and p-orbital magnetism is only suggested in impurity bands with small ferromagnetic moments. The present work provides a new route for creating ferromagnetism in semiconductors and exploring new p-orbital physics and chemistry. In addition, the material shows elastic-mechanoluminescence that may enable unprecedented mechano-photonic-spintronics.
固体中的氧通常以O离子态存在。因此，它失去了单个原子的磁性，在其外层2p轨道中有两个未配对电子。在此，研究表明在一种新型半导体材料SrAlO中实现了一种非常规的稳定O离子态，从而导致一种本征p轨道铁磁性，这种铁磁性在约900 K以下保持稳定。实验和理论研究已阐明，SrAlO晶体结构中四分之一的氧原子键合不充分，从而导致独特的O态和p轨道铁磁性。迄今为止，据报道O态仅存在于非平衡条件下，而p轨道磁性仅在具有小铁磁矩的杂质带中被推测存在。本工作为在半导体中创造铁磁性以及探索新的p轨道物理和化学提供了一条新途径。此外，该材料表现出弹性机械发光，这可能促成前所未有的机械光子自旋电子学。
